Safety electrode holder for arc welding



Dec 9, 1941 F. w. HACKMEYER 2,265,135

SAFETY ELEcTRonE HOLDER FOR ARC WELDING Filed Feb. 12, 1940 gig. v O

, 51' 24g/fil jjj? F. HACKMEYER,

Patented Dec. 9, 1941 UNITED sTATEs PATENT OFFICE SAFETY ELE("RODE HOLDER FOR ARC WELDING Ferdinand W. Hackmeyer, Mobile, Ala.

Application February 12, 1940, Serial No. 318,581

8 Claims.

'. eyes, should the current pass through the device at a time when his eyes were not adequately shielded. This problem has been recognized by others and it is the principal object of the present invention to provide improved and simplified cut-oil' mechanism for such electrode holders.

The present application is in the nature of an improvement on the device disclosed in my prior application Serial No. 276,427 led May 29, 1939, now Patent No. 2,236,849 dated April 1, 1941. In common with the disclosure of my prior application, the electrode holder is preferably of the expansible jaw type, and includes a movable cable or conductor carrier housed within a hollow insulating handle, said carrier in one position completing the circuit through the holder from the cable to the electrodes and in another position breaking said circuit. According to my prior application, means are provided whereby the opening of the cut-o switch must precede the opening of the jaws, and according to the present applica-tion the switch is automatically opened as the jaws are separated or just prior to the opening of the jaws, this being one of the important features of the invention.

Another feature of the invention resides in the improvement of the holding jaws.

Still another feature resides in the improvement of the switch mechanism.

A further feature resides in improvement of the cable attaching means.

The 'invention will be more readily understood by reference to the accompanying drawing and the following detailed description which are given by way of illustration rather than by way of limitation.

In the drawing:

Fig. 1 is a view partly in elevation and partly in longitudinal section showing one form of the electrode holder in normal or working position.

Fig. 2 is a similar view showing the automatic opening of the switch just prior to the opening of the electrode holding jaws.

Fig. 3 is a detail perspective view showing the electrode clamping jaws. l

Fig. 4 is a front view of the same.

` numerals I0,

Fig. 5 .is a section on the line 5-5 of Fig. 1, and

Fig. 6 is a view partly in longitudinal section and partly in side elevation showing a different form of electrode holder embodying the automatic feature of the invention.

Referring to the drawing in detail the reference II indicate a pair of electrode clamping jaws pivoted at I2 and adapted to retain a number of electrodes inserted transversely or a single electrode inserted longitudinally. The jaw III is cut away at the center as indicated at I3 and the jaw I I is provided with a longitudinal rib vI4 projecting downwardly. By reason of this construction of jaws I0 and II a three point support for tmsversely inserted electrodes is provided.

As shown the jaw I0 forms an extension of a conductor member I5 mounted at the front end described. The handle may be provided with an integral guard member M similar to that disclosed in my prior application Serial No. 276,427 filed May 29, 1939.

The jaw II is provided with an upwardly ini clined extension I1 having a socket I8 formed therein to receive one end of a spring I9, the other end of which lits in the socket 20 and serves to normally hold the jaws closed.

At the end of the inclined member I'I is a xed portion 2l whose lower face is shown as substantially parallel with the face of the jaw II. To this member is pivotally connected a supplemental member 22 having an inclined surface 23 and an outwardly projecting end portion 24. The fixed member 2| and hinged member 22 are mounted within the tubular insulating jacket 26 which is provided with an opening or slot 2l near the bottom thereof. The jacket 26 is held in place by the pivot pin which connects the members 2l and'22.

Pivotally mounted at 3I within the handle I6 is a cable carrier 28 which is shown as provided with a plurality of longitudinal slots to facilitate insertion of the cable 29 which is then retained in positionby rings 30. Projecting forwardly from the cable carrier 28 is a conductor member 32 a provided with a copper plate 33 adapted to coact with a corresponding plate 34 secured to the fixed conductor I 5. A spring 35 normally urges the i handle to permit access to the spring in assembling the device.

The automatic switch mechanism includes a bell crank member 31 shown as pivoted at 38 in the handle I5 which is slotted at its upper portion to receive the bell crank. One arm 39 of the bell crank extends upwardly and its end projects through the slot 21 in the insulating jacket 26 and is adapted to engage the end portion 24 of the pivoted member 22. The other arm 40 of the bell crank projects downwardly and has pivoted thereto a member 4I which is provided with a cam surface 42 adapted to engage a similar inclined surface 43 formed on the conductor mem- When it is desired to remove or insert an electrode or electrodes the insulating handles I6 and 26 may be grasped bythe hand of the operator and squeezed together leaving the other hand free. 'I'he first effect of this operation is to move the parts from the position shown in Fig. 1 to that shown in Fig. 2 vthereby disengaging the contact plates 33 and 34 and breaking the circuit. Further movement of the handle members I6 and 26 toward each other serves to open thejaws IIJ and II and permits insertion or removal of an electrode or electrodes. This being accomplished the handle 26 is released whereupon the spring I9 cornes into effect, closing the jaws I0 vand II after which the spring 35 comes into effect forcing the plates 33 and 34 into contact and closing the circuit through the handle from the cable 29 to the electrodes held by the clamping jaws I and II.

Fig. 6 shows how the automatic feature may be adapted to an electrode holder including a cable carrier of the sliding type similar to that disclosed in my application Serial No. 276,427 filed May 29, 1939. As shown the jaws Illa and IIa are similar to the .corresponding jaws of the first described embodiment of the invention and are pivoted at I 2a. The body I0a forms an extension of a conductor Ia which is secured in the front portion of an insulating handle I5a.. The body IIa is provided with an upwardly inclined portion Ila having a socket I8a formed therein to receive one end of the spring I9a the other end of which engages in the socket 20a, the spring serving to hold the jaws closed. At the upper end of the inclined portion I1a is a fixed portion 2Ia substantially parallel to the face of the jaw IIa. A movable member 22a is pivotally connected to the fixed member 2Ia and in the present case the member 22a is of insulating material and adapted to be grasped by the operator when the jaws are to be opened. 'I'he cable carrier v5I) is of the sliding type and is adapted to receive a cable 5I which is herein shown as provided with a metal cap 52 preferablyof cop? per and a steel pin 53 which holds the cable in place and extends into the cable. The cable is secured at the rear end of the cable carrier. 'I'he carrier is urged into contact with a copper plate 53a at the rear of the conductor I5a by means ofa pair of expansible members 54, 54 accessible through removable members 55, 55 in the holder,

as set forth in my prior application Serial No. 276.427 filed May 29, 1939.

' The holder is provided with a slot 56 through which projects an operating member 51 xed to the end of the cable carrier and serving to reciprocate the same. The operating member is shown as inclined forwardly and is adapted to be engaged by the rear end of the insulating member 22a'. A

The operation is similar to that described in the preceding embodiment of the invention. When the handle members 22a and I6a are grasped thel flrst'eifect is to pivot the member 22a with reference to the member 2Ia thereby engaging the operating member 51 and forcing the cable carrier rearwardly thus breaking the circuit at the contact plate 53. Further grasping movement opens the jaws Illa, IIa permitting insertion or removal of the electrode or electrodes.

Thus according to both embodiments of the invention an automatic switch is provided to break the circuit through the electrode holder prior toA the opening of the holder jaws.

The invention has been described in vdetail for the purpose of illustration but it will be apparent that modifications and variations may be resorted to without departing from the spirit of the inat any place where thereis danger of arcing, the A operator may manually press the member 39 forwardly further than would ordinarily be the case .when the holders 26 and I6 are merely pressed together, whereupon the member 4I `will move far enough to get upon the straight part between'members I5 and 32 and thus hold indefinitely or until released by pressing down on the rear end of the member 39 which will insure safety from arcing. This eliminates danger of ashing an arc in the eyes of the operator or helpers when not ready.

I claim:

1. In a safety electrode holder having expans ible jaws, a hollow handle connected to one of the jaws, switch means including la cable carrier movably mounted within the handle and adapted to make and break a circuit through said holder, a second handle connected to the other of said jaws and `means actuated by movement of the second handle for automatically operating the cable carrier to break said circuit prior to opening the jaws.

2. In an electrode holder or the like, having electrode gripping jaws, a hollow handle connected to one of the jaws, a cable carrier pivotally mounted within the handle at the rear thereof, a conductor member carried at the front end of the handle, contact plates carried by the cable carrier and conductor member respectively, means normally urging the contact plates into engagement with each other, an operating member pivotally mounted within the handle having means engaging the cable carrier for forcing the same out of contact with said conductor member, and a second handle connected to the other of said jaws having means associated therewith for actuating the pivoted operating member.v

3. A safety electrode holder having expansible electrode gripping jaws, handles connected to electrode gripping jaws, handle members associated with said jaws, a switch member carried by one of said handle members which in one position serves to close a circuit through said jaws and in another position to open said circuit, and means associated with the other of said jaws and cooperating with said switch, serving to move the switch to open circuit position prior to the initial opening of the gripping jaws.

5. In a welding tonghaving handles and a gripping member and means urging said gripping member into gripping or closed position; a switch formed in one handle for making and breaking the circuit to said gripping member and including means cooperatively related to` said other handle and controlled thereby to open said switch and break the circuit to said tong when said gripping member is opened. said means being movable to circuit closing position when said grippingmember is clod.

6. In combination with a welding tong having a gripping member and handle elements therefor; a handle for one of said elements and a combined handle and switch for the other element and means associated with said one of said elements actuating said switch to break the circuit to said welding tong when said gripping member is opened.

'7. In a safety electrode holder having expansible gripping jaws, means normally urging the jaws into gripping or closed position, a hollow handle member rigidly connected with one of saidy U0 member.

jaws, a second handle member associated with the other of said jaws, a cable mounted within the hollow handle, a switch formed within the hollow member formaking and breaking a circuit from said cable to said expansible jaws, and including switch actuating means cooperatively related to said other handle member and controlled thereby to open said switch and break the circuit to said jaws when the said gripping jaws are opened, said means being movable to circuit closing position when said jaws are closed.

8. In a safety electrode holder having expansible gripping jaws, means normally urging the jaws into gripping or closed position, a hollow handle member rigidly connected with one of said jaws, a second handle member associated with the other of said jaws, a cable mounted within the hollow handle, a switch formed within the hollo'w member for making and breaking a circuit from said cable to said expansible jaws, and including switch actuating means cooperatively related to said other handle member and controlled lthereby to open said switch and break the circuit to said jaws when the said gripping jaws are opened, said means being movable to circuit closing position when saidljaws are closed, said switch operating means comprising a projection extending through a slot in the hollow member into -the path of the Vsecond handle 

